Advances in the cell biology of transport via the inner blood-retinal barrier: Establishment of cell lines and transport functions

Ken Ichi Hosoya, Masatoshi Tomi

Research output: Contribution to journalReview article

103 Citations (Scopus)


The retinal capillary endothelial cells are connected to each other by tight junctions that play a key role in permeability as the inner blood-retinal barrier (inner BRB). Thus, understanding the inner BRB transport mechanism is an important step towards drug targeting of the retina. Nevertheless, inner BRB transport studies have been very limited in number since it is not easy to use the retinal capillaries, which are very small in size, for in vitro transport studies. Conditionally immortalized rat retinal capillary endothelial cells (TR-iBRB), pericytes (TR-rPCT) and Müller cell lines (TR-MUL) have been established from transgenic rats harboring the temperature-sensitive simian virus 40 large T-antigen gene. These cell lines posses respective cell type markers and maintain certain in vivo functions. Using a combination of newly developed cell lines and in vivo studies, we have elucidated the mechanism whereby vitamin C, L-cystine, and creatine are supplied to the retina. TR-iBRB cells are also able to identify transporters and apply to study regulation of transporters under pathophysiological conditions. Furthermore, these cell lines permit the investigation of cell-to-cell interactions and the expression of inner BRB-specific genes between TR-iBRB and other cell lines.

Original languageEnglish
Pages (from-to)1-8
Number of pages8
JournalBiological and Pharmaceutical Bulletin
Issue number1
Publication statusPublished - 2005 Jan
Externally publishedYes



  • Blood-ocular barrier
  • Cell-to-cell interaction
  • Conditionally immortalized cell line
  • Inner blood-retinal barrier
  • Transport function
  • Transporter

ASJC Scopus subject areas

  • Pharmacology
  • Pharmaceutical Science

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